Reviewed by USGSTonga76y ago
M7.8 earthquake 159 km W of Pangai, Tonga
Thursday, December 14, 1950, 01:52:54 UTC · 19.705°S, 175.874°W
A magnitude 7.8 earthquake struck 159 km W of Pangai, Tonga on Thursday, December 14, 1950, 01:52:54 UTC, at a depth of 215.9 km (intermediate). It is the strongest earthquake within 300 km since an M7.8 on January 1, 1919.
- Magnitude
- 7.8
- Major · mw
- Depth
- 216 km
- Intermediate
- Felt reports
- 0
- Did You Feel It?
- Est. shaking
- —
- No ShakeMap
- PAGER alert
- None
- Not issued
- Tsunami
- No flag
- USGS feed
Outlined circle: this earthquake
In context
How big was it, and why here?
Energy released
7.6 megatons of TNT
That is about 502 times the Hiroshima bomb. It released about 15,849 times the energy of a magnitude 5.0.
Tectonic setting
17 km
from the nearest mapped plate boundary, between the Tonga and Australian plates. Earthquakes cluster along boundaries like this one, where plates collide, pull apart or slide past each other.
Depth: intermediate
216 km
Intermediate-depth earthquakes usually break inside a plate that is sinking into the mantle. Shaking spreads over a wide area but is gentler at the epicenter than a shallow quake of the same size.
Did You Feel It?
Where it was felt
No “Did You Feel It?” reports have been published for this event yet. If you felt it, you can add your report on the USGS website.
I felt it — report to USGS ↗USGS PAGER estimate
Who was exposed to shaking
USGS publishes PAGER impact estimates for significant earthquakes, usually within an hour. No PAGER estimate is available for this event.
After the main event
Aftershocks within 200 km
USGS has not published any M2.5+ earthquake within 200 km in the 30 days after this event.
Regional history
Past M5+ earthquakes within 300 km
USGS lists 54 M5.0+ earthquakes within 300 km before this one (catalog from 1900; older records are less complete). The strongest:
- 8.0TongaJanuary 4, 1903 · 97 km E of this epicenter
- 7.8Fiji regionJanuary 1, 1919 · 235 km W of this epicenter
- 7.8111 km SSE of Pangai, TongaJune 26, 1913 · 241 km SE of this epicenter
- 7.5110 km E of ‘Ohonua, TongaSeptember 8, 1948 · 267 km SE of this epicenter
- 7.385 km ESE of Neiafu, TongaJanuary 2, 1907 · 278 km E of this epicenter
- 7.3227 km WNW of Haveluloto, TongaApril 16, 1937 · 180 km SW of this epicenter
- 7.2108 km SE of Neiafu, TongaDecember 19, 1906 · 290 km E of this epicenter
- 7.2241 km WNW of Houma, TongaAugust 21, 1911 · 149 km W of this epicenter
History · NOAA
Deadliest earthquakes in this area
NOAA’s significant-earthquake database lists 12 damaging, deadly or tsunami-generating earthquakes within 300 km of this epicenter since 1700. The most severe:
- 1865M8.0
Tonga Islands
18 Nov 1865 · 250 km away
Limited damage (under $1M)tsunami
- 1937M8.1
Fiji Islands
16 Apr 1937 · 231 km away
- 1903M8.0
Tonga Islands
4 Jan 1903 · 97 km away
- 1948M7.9
Tonga Islands
8 Sep 1948 · 243 km away
tsunami
- 1902M7.8
Tonga Islands
9 Feb 1902 · 199 km away
- 1919M7.8
Fiji Islands
1 Jan 1919 · 235 km away
tsunami
NOAA NCEI Global Significant Earthquake Database. Historical figures are estimates; older records are incomplete.